Theoretical cost benefits of cryobiopsy

To the Editor:

I commend the study by Schumann and colleagues1 that demonstrated the clear superiority of cryobiopsy over standard forceps biopsy for endoluminal tumor, showing a 36% relative increase and 24% absolute increase in yield as the result of larger and less fragmented samples.1 Unfortunately, the acquisition of new equipment and technology is hampered by resource rationing in health care systems. Because tariff-base health care systems require demonstration of cost benefit, this article provides useful evidence with which to develop cryobiopsy in bronchoscopy units. At Glenfield Hospital, Leicester, which includes an annual number of 531 fiberoptic bronchoscopies annually, we have audited our own diagnostic yield with forceps biopsy for endoluminal tumor and found this to be only 77% overall for 132 cases over 1 year with evidence of tumor (with some variation between trainees and consultants).2

By assuming a similar number of bronchoscopies per year with endoluminal tumor with a similar yield with forceps biopsy, this equates to 30 nondiagnostic bronchoscopies (Table 1). Under the National Tariffs for 2010 and 2011,3 the total extra annual cost is calculated to be more than £15,000 per year to the Primary Care Trust 9 (Table 1). By assuming a relative increase in performance with cryobiopsy similar to that reported by Schumann and colleagues,1 this would translate to a cost savings of more than £15,000 per year (Table 1). The capital cost of the cryobiopsy equipment (£7500, ERBE Medical UK, personal communication, May 2010) could be covered by saving 15 repeat bronchoscopies, which would take an estimated 6 months (at 30 saved per year; Table 1). After 1 year, residual cost savings would total more than £6500 despite deductions for capital, maintenance, and consumable costs (Table 1). For subsequent years, residual funds would be in excess of £14,000 (Table 1).

Table 1. Breakdown of extrapolated cost benefits of cryoprobe

	Diagnostic yield with forceps biopsy at Glenfield Hospital, Leicester (%)	77%
	Repeat bronchoscopy rate (%)	23%
	No. of bronchoscopies with macroscopic tumor/year	132
	No. of repeat bronchoscopies needed/year (132 × 23%)	30
	Cost of standard bronchoscopy (2010 tariff)	£504
	Published improved relative increase in yield with cryobiopsy (%)	36%
	Estimated diagnostic yield with cryobiopsy at Glenfield Hospital, Leicester (36% relative increase on 77%) (%)	100%
	Cost saving of cryobiopsy to Primary Care Trust (£504 × 30)	£15,120
	Cost of cryobiopsy equipment (cryosurgery unit and cable, adapter, probes, gas tube, footswitch)	£7,500
	No. of bronchoscopies to prevent to cover costs (7500/504)	15
	Total annual costs (service contract + consumables)	£955
	Residual cost savings after capital costs (15,120 – 7500)	£7,620
	Residual cost savings after annual costs (7620 – 955)	£6,665
	Residual cost savings, year 2 onward (15,120 – 955)	£14,165

The data provided by Schumann and colleagues1 give respiratory physicians the opportunity to provide a robust financial case for adding cryobiopsy to their bronchoscopy unit on the basis it will fund itself in 6 months, according to our own calculations and experiences. In addition, better quality biopsies will provide better material for bronchoscopic tissue research studies and molecular markers.4